I've got the msd pro billet distributor hooked up to the mds 6al ignition, to a msd blaster 3 coil. awesome awesome awesome. totally recommend it. luv the rev limiter, the gas mileage is much better, and response is awesome. would go that route ten times over. all together ran me about five bills.
I bought it direct from Jacobs several years ago. It ran just under $400. I have the Ultra team deal. Drawbacks to the system
1) The kill switch falls apart quickly. Don't use it, it will only leave you stranded at the most inopportune time.
2) basic plug wires don't like header heat. Keep the wires away from the exhaust.
Other than that, the truck has been starting in less than 1 second, even in all this sub-zero weather. My battery is happy about that. Jacobs also makes it easy to convert to their system. I made a bracket to keep my old coil handy incase the Jacobs system craps out.
everyone who gets the MSD stuff is also happy with theirs. It's just paying the price that is hard to swallow.
i bought a D.U.I. distributor. Davis Unified Ignition. it is a business out of tennesse. They take the specs of your engine, what you want to do with it, and built, set the curve. all you do is drop it in. the best part is they use GM solid state parts (easy/cheap to replace) they run around $450.